I've built Solarite, a library that's made vanilla web components a lot more productive IMHO. It allows minimal DOM updates when the data changes. And other nice features like nested styles and passing constructor arguments to sub-components via attributes.
It's ok now, at least for me. There are still challenges around theming and styling because of styling boundaries (which makes Web Components powerful, but still). A part of it is about tooling, which can be easier to improve.
I find Web Components aren't as much of a pain to write if you ignore the Shadow DOM. You don't need the Shadow DOM, it is optional. I don't think we are doing ourselves too many favors in how many Web Component tutorials start with or barrel straight into the Shadow DOM as if it was required.
It's a shame Surplus (Adam Haile's, not my succession of it) isn't cited nor is he mentioned, given that at least two of the listed frameworks were heavily and directly inspired by his work. S.js is probably one of the most incredible JavaScript libraries I've used that should be the reference for a signal API, in my opinion.
